Growth hormone & endocrine research
Tesamorelin (Egrifta SV): Research, Mechanism & Current Evidence
GHRH analogue approved for HIV-associated excess abdominal fat; studied for visceral fat specifically.
Also known as Egrifta · TH9507 · GHRH (1-44) analogue · Egrifta SV
What is Tesamorelin?
Tesamorelin is a synthetic analogue of growth hormone-releasing hormone, stabilised so it lasts longer than the natural hormone. It is sold as Egrifta.
It is one of the few compounds in this area with a genuine regulatory approval: the FDA approved it in 2010 for excess abdominal fat in people with HIV-associated lipodystrophy.
Status: Approved by the FDA for HIV-associated lipodystrophy. Prohibited in sport by WADA.
What is Tesamorelin researched for?
Visceral fat — the fat stored around the organs rather than under the skin — is the specific target, and the distinction matters because the two behave differently in metabolic research.
Later work has examined liver fat in fatty liver disease and cognitive measures in older adults.
- FDA-approved indication showing 15-20% visceral fat reduction in clinical trials.
- Unique mechanism that reduces dangerous visceral fat while sparing subcutaneous fat.
- Maintained weight loss with continuous treatment over 52+ weeks in clinical studies.
- 12.3% reduction in triglyceride levels.
- 7.2% improvement in cholesterol markers.
- 37% liver fat reduction over 12 months.
- Preserves lean muscle mass during fat loss.
- 26% increase in IGF-1 levels.
How does Tesamorelin work?
Tesamorelin acts on the GHRH receptor in the pituitary gland, prompting release of the body's own growth hormone in its normal pulsed pattern rather than supplying growth hormone directly.
Growth hormone in turn promotes the breakdown of stored fat, and visceral fat appears to be particularly responsive.
Reported targets: GHRH receptor
What does the research show?
Registration trials in people with HIV-associated lipodystrophy reported visceral fat reductions in the region of 15 to 20% over 26 to 52 weeks, with subcutaneous fat largely preserved.
A separate randomised trial reported reductions in liver fat in people with HIV and fatty liver disease.
Limitations of the current evidence
The approved population is specific. Trials were conducted in people with HIV-associated lipodystrophy, and the results should not be assumed to transfer to general weight management.
Visceral fat returns after stopping, and effects on glucose tolerance need monitoring in trials because growth hormone can reduce insulin sensitivity.
References
Metabolic effects of a growth hormone-releasing factor in patients with HIV
Falutz J, Allas S, Blot K, et al. · The New England journal of medicine · 2007
Pivotal Phase III trial in 412 HIV patients. Tesamorelin 2mg daily for 26 weeks significantly decreased visceral fat and improved lipid profiles compared to placebo.
Controlled clinical trial · PMID 18057338
Effects of Tesamorelin in HIV-Infected Patients with Abdominal Fat Accumulation: Randomized Placebo-Controlled Trial with Safety Extension (CTR-1011)
Falutz, J., et al. · Journal of Acquired Immune Deficiency Syndromes · 2010
404 HIV patients treated for up to 12 months. 69% achieved ≥8% VAT reduction vs 33% placebo. VAT benefits were lost upon discontinuation, confirming need for continuous therapy.
Controlled clinical trial
Effects of Growth Hormone-Releasing Hormone on Cognitive Function in Adults with MCI and Healthy Older Adults Baker, L.D., et al. Archives of Neurology
2012
152 adults (ages 55-87) treated with tesamorelin 1mg daily for 20 weeks. Favorable effect on cognition (P=0.03), with particular benefit on executive function (P=0.005) and IGF-1 increase of 117%.
Stanley TL, Fourman LT, Feldpausch MN, et al. · The lancet. HIV · 2019
61 HIV patients with NAFLD randomized to tesamorelin 2mg vs placebo for 12 months. 37% relative reduction in hepatic fat fraction (P=0.02), with prevention of fibrosis progression on liver biopsy.
Controlled clinical trial · PMID 31611038
Body Composition, Hepatic Fat, Metabolic, and Safety Outcomes of Tesamorelin: A Meta-Analysis of Randomized Controlled Trials
Elgenidy, A., et al. · HIV Medicine · 2025
Meta-analysis of 5 RCTs showing significant VAT reduction (MD=-27.71 cm², P<0.001), increased lean body mass (MD=1.42 kg, P<0.001), and improved hepatic fat and IGF-1 levels without serious safety concerns.
Controlled clinical trial
Baker LD, Barsness SM, Borson S, et al. · Archives of neurology · 2012
PMID 22869065
Falutz J, Potvin D, Mamputu JC, et al. · Journal of acquired immune deficiency syndromes (1999) · 2010
Controlled clinical trial · PMID 20101189
Badran AS, Helal A, Shata KS, et al. · Obesity research & clinical practice · 2026
Controlled clinical trial · PMID 41545261
Common questions
Does tesamorelin specifically target visceral fat or does it reduce overall body fat?
Tesamorelin uniquely targets visceral (deep abdominal) fat while sparing subcutaneous fat. This selective mechanism makes it FDA-approved specifically for HIV-associated lipodystrophy - the visceral fat reduction of 15-20% occurs without proportional subcutaneous fat loss, improving metabolic health and reducing cardiovascular risk.
Why use tesamorelin over semaglutide for visceral fat loss?
Tesamorelin uniquely spares subcutaneous fat while targeting visceral fat, making it better for patients wanting to preserve healthy fat deposits. Semaglutide causes general weight loss across all fat depots. Choose tesamorelin for selective visceral fat reduction in metabolically healthy individuals; semaglutide for comprehensive weight loss.